Tamper-evidencing container and closure structures

ABSTRACT

Tamper-evidencing container and closure structures are provided for preventing or for signaling unauthorized access to packaging. These structures provide tamper-evidencing improvements that add to the security and reliability of packaged contents.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates, in general, to tamper-evidencing container and closure structures and methods for their use.

2. Description of Related Art

Consumer packaging widely incorporates tamper-evidencing mechanisms to protect contents from tampering prior to purchase and use. One widely used technique is to incorporate visible structure into the packaging which must be altered or destroyed during initial opening of the package. The alteration supplies visible evidence that the package has been previously opened.

When a package includes a container and closure, a common approach is to include a tamper indicating band as part of the closure. The tamper indicating band may depend from a lower edge of a closure's cylindrical annular skirt through a frangible of weakened line. Most often, a form of retaining structure is positioned on an interior portion of the depending band. This retaining structure is intended to engage cooperative structure positioned on the exterior of the container as the closure is initially applied to the container. The engagement of the cooperative band and container retaining structures restricts upward axial movement of the band during initial closure removal. Thus, the band is separated from the upper portion of the closure along the weakened joining line to allow (or as a result of) initial closure removal.

Often the cooperating tamper-evidencing structure on the container includes an outwardly directed flange or projection on the exterior of the container neck. A radially inwardly projecting structure on the interior region of the closure tamper-evidencing band slides over the container flange with the axially downward movement associated with initial closure application. The inwardly directed band structure comes to rest below the container flange to restrict subsequent upward closure movement and initial removal without separating the band from the upper portion of the closure along the line of weakness.

Quintessential examples of tamper-evident packaging incorporating radially interfering closure band structure cooperating with container structure are taught in U.S. Pat. No. 4,166,552 to Faulstich, and U.S. Pat. No. 6,484,896 to Ma, both of which are herein incorporated in their entirety by reference. Faulstich teaches a snap-on/pull-off closure incorporating a tear-away tamper band. As initially applied a simple inwardly directed bead on the Faulstich closure rests below a projecting bead on the container neck. The band must be torn away to release this bead interference prior to pulling the closure off the container. As is known in the art, tear away bands are normally associated with a choice of low-density polyethylene for the closure. This material also allows for facile snap-on/pull-off operation of closures. Ma discloses a closure whose tamper indicating band has the form of the letter “J” and thus this type band is often referred to as a “J-band”. After initial application of the Ma closure, the upward-inward portion of the “J” structure is directed toward the underside of a projecting container bead in radially interfering position. As the closure moves axially upward during initial removal, the radial interference between the upward-inward band portion and the container bead retains the band to cause the band to break away from the closure along the line of weakness. The “J-band” mechanism has achieved widespread application for closures formed of relatively rigid materials, such as polypropylene, often chosen for screw caps.

Unfortunately, as will be explained below, the relatively simple concept of interfering tamper band cooperating with a container flange is often compromised by required material characteristics, processing variations and achievable tolerances of the structural details. Indeed, in some cases an unscrupulous individual, given sufficient time, privacy and resources may be able to manipulate the closure in a way to achieve its removal without activating the visible destruction of the joining between the closure annular skirt and tamper band. Therefore, there is a need for improved designs to further increased reliability of band retention in such tamper-evident systems, for improved closure and container structural elements to improve reliability of tamper indicating packaging, and for impeding initial removal of a closure from a container absent the visible tamper indicating signal intended during such removal.

BRIEF SUMMARY OF THE INVENTION

One aspect of the present invention is directed to a tamper-evidencing closure including a top, an annular skirt depending from the top, a tamper-evidencing band frangibly connected to the bottom of the annular skirt, an inwardly-turned retaining rim that extends at least partially upwardly from the tamper-evidencing band, the retaining rim having a free edge adapted for engagement with a locking surface of a container, and an anti-collapsing extension extending from the free edge of the retaining rim. Preferably, the anti-collapsing extension is dimensioned and configured to oppose collapse and distortion of the retaining rim when an upward force is applied to the closure while the free edge is engaging the locking surface.

In one embodiment, the anti-collapsing extension may have a rectangular shape. The anti-collapsing extension may have a substantially square-shaped cross-section. The tamper-evidencing closure may further include a plurality of anti-collapsing extensions extending from the free edge of the retaining rim. The anti-collapsing extensions may be circumferentially spaced around the retaining rim. The tamper-evidencing closure may further include a plurality of flutes located between adjacent arcuate segments of the retaining rim. At least one anti-collapsing extension may be located between adjacent ones of said flutes. The tamper-evidencing closure may further include vertically-extending lines of weakness circumferentially spaced about the annular skirt. The lines of weakness may be located on an inner surface of the annular skirt.

Another aspect of the present invention is directed to the above-mentioned tamper-evidencing closure in combination with a tamper-evidencing container, said container. The container may include a container neck finish having closure-engaging structure dimensioned and configured for engaging the closure upon reclosure, and a locking surface on the container neck finish below the closure-engaging structure. The locking surface may be dimensioned and configured to engage the free edge of the retaining rim of the closure. The anti-collapsing extension of the closure may extend between the locking surface of the container and the annular skirt of the closure when the closure is fully applied to the container. The combination may further include an inward taper on an exterior surface of the container neck finish below said locking surface. The inward taper may be dimensioned and configured to increase hoop strength of the exterior surface. The inward taper may be formed by an inwardly-concave stretch. The combination may further include another inwardly-concave stretch formed in another exterior surface of the container neck finish, the another inwardly-concave stretch being dimensioned and configured to increase hoop strength of the another exterior surface.

The tamper-evidencing container and closure structures of the present invention has other features and advantages which will be apparent from or are set forth in more detail in the accompanying drawings, which are incorporated in and form a part of this specification, and the following Detailed Description of the Invention, which together serve to explain the principles of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side elevational view in section of a prior art closure and complimentary container finish just prior to initial application of the closure to the container.

FIG. 2 is a sectional, side elevational assembly view of the closure and container finish of FIG. 1 following initial application of the closure to the container.

FIG. 3 is a side elevational view of the closure of FIG. 1 showing the structure for proper initial closure removal and the resulting tamper-indicating result.

FIG. 4 is a side elevational view of the closure of the FIG. 1 assembly reacting to an improper attempt to remove the closure.

FIG. 5 illustrates another approach which has been employed to effect unauthorized removal of the prior art closure of FIG. 1.

FIG. 6 is an enlarged side elevational view in section of the prior art closure of FIG. 1 applied to an another prior art container finish.

FIG. 7 is a side elevational view in section of yet another prior art closure, with the sectional view taken substantially from the perspective of lines 7-7 of FIG. 9.

FIG. 8 is an enlarged view of a portion of the closure of FIG. 7, said portion encircled and identified 8-8 in FIG. 7.

FIG. 9 is a bottom view of the closure of FIG. 7.

FIG. 10 is a side elevational view, partially in section, of a container neck finish complimentary to the closure of FIG. 7.

FIG. 11 is a side elevational view, partly in section, of the closure of FIG. 7 initially applied to the finish of FIG. 10.

FIG. 12 is a side elevational view in section showing the closure of FIG. 1 as initially applied to an improved container neck finish according to the present invention.

FIG. 13 is a cross-sectional view of the closure and neck finish of FIG. 12 taken substantially along line 13-13 of FIG. 12.

FIG. 14 is a cross-sectional view of another improved closure and complimentary container finish according to the present invention.

FIG. 15 is a perspective cross-sectional view of yet another improved closure according to the present invention.

FIG. 16 is an enlarged cross-sectional view of a portion of the closure of FIG. 15, said portion encircled and identified 16-16 in FIG. 15.

FIG. 17 is a cross-sectional side view of an improved container finish according to the present invention useful in conjunction with the closure shown in FIG. 1.

FIG. 18 illustrates the response to unauthorized removal of the closure of FIG. 17 when used with the improved container finish of FIG. 17.

FIG. 19 is a cross-sectional side view of yet another closure and complimentary container finish according to the present invention.

FIG. 20 is a perspective cross-sectional view of another closure design according to the present invention.

FIG. 21 is an enlarged cross-sectional view showing the details of the structure circumscribed in FIG. 20.

FIG. 22 is an exploded cross-sectional view of the closure of FIGS. 20 and 21 just prior to application to a complimentary container neck finish.

FIG. 23 is a perspective cross-sectional view of the closure of FIGS. 20 and 21 initially applied to the complimentary container neck finish of FIG. 22.

FIG. 24 is a bottom perspective view, partially in section, of yet another closure according to the present invention.

FIG. 25 is an enlarged perspective cross-sectional view showing a portion of the closure of FIG. 24, said portion circumscribed and identified 25-25 in FIG. 24.

FIG. 26 is an enlarged perspective cross-sectional view of the closure of FIG. 24 initially applied to a complimentary container neck finish.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. While the invention will be described in conjunction with the preferred embodiments, it will be understood that they are not intended to limit the invention to those embodiments. On the contrary, the invention is intended to cover alternatives, modifications and equivalents, which may be included within the spirit and scope of the invention as defined by the appended claims.

Turning now to the drawings, wherein like components are designated by like reference numerals throughout the various figures, attention is directed to FIGS. 1-5, in which there is shown a well known complimentary closure and container arrangement. In FIG. 1, closure 10 includes a top 11 having bottom side 12. Top 11 often is a simple circular disk, but can take other appropriate forms as is known in the art. Depending from the bottom side 12 is annular closure skirt 14. In the embodiment shown, skirt 14 has cylindrical form with substantially smooth outside surface 16 and internal wall 17. Positioned on the internal wall 17 of skirt 14 are container retention structures 18 and 20. Both structures 18 and 20 include bead-like formations projecting radially inwardly from the internal wall 17. As is known in the art, structures 18 and 20 can extend essentially continuously around the circumference of skirt 14 or be interrupted in the form of multiple individual segments. Skirt 14 also includes a line of weakness, often referred to as a score line, identified as 22 in the drawings. In the embodiment of FIGS. 1-4, score line 22 extends horizontally around the entire circumference of skirt 14, defining an upper skirt portion 24 and lower skirt portion 26. As best seen in FIG. 4, an additional branch score line 28 extends in an arcuate path from horizontal line 22 to the lower edge 30 of skirt 14. Also seen in FIG. 4 is pull tab 32 extending downward from the lower edge 30 of skirt 14 and positioned adjacent branch score line 28.

Closure 10 also includes a seal plug 34 depending from the bottom side 12 of top 11 and is positioned radially inwardly of skirt 14. In the illustrated embodiment, and as is well known in the art, seal plug 34 is in the form of a hollow cylinder. Closure 10 also includes a thin, flexible flange structure 36 extending radially outwardly of the exterior surface 16 of skirt 14. Flange 36 promotes facile manual manipulation of the closure when properly used and extends the top surface area available for label placement.

Continuing to refer to FIG. 1, there is also shown a container neck finish 37 whose design is functionally complimentary to closure 10. Finish 37 generally includes a circular structure 38 surrounding an orifice leading to the internal portion of the container. Finish 37 has an outside surface 40 having a functionally designed contour as best seen in FIG. 1. Surface 40 extends essentially vertically downward from the top 42 of finish 37 for a distance, then extends radially inwardly before continuing to extend downwardly for an additional distance. It then continues to extend in a downwardly-outwardly directed slope to an apex 44. Below apex 44, the wall surface projects radially inwardly to vertical segment 46. At the base of vertical segment 46 the surface assumes another downward-outward slope to reach a predefined diameter before merging with the remainder of the container body at a point generally indicated by numeral 48. As is seen in FIG. 1, this contour structure results in two outward projections 50 and 52 having a horizontal component associated with their bottom surfaces 54 and 56 respectively.

Finish 37 also includes an inwardly directed flange 58 at its top portion. As is known in the art, the inner edge 60 of flange 58 can serve as a primary seal surface in cooperation with closure plug 34.

FIG. 2 shows the result of applying closure 10 to finish 37. This application is most often accomplished by a direct axial force applied to closure 10 to “push” closure 10 onto the container finish 37. As this axial application is achieved, the container retention structures 18 and 20 of closure 10 slide over projections 50 and 52 of the container finish 37. Following complete application, retention structure 18 of closure 10 rests under finish projection 50 and retention structure 20 of closure 10 rests under finish projection 52. This combination of interferences is designed to produce a very secure retention of the closure to the container. For example, as is shown in FIG. 4, if one attempts to remove the closure by simply pulling it off, the flexibility of the flange 36 prevents asserting sufficient leverage to overcome the dual retention interferences 18/50 and 20/52. Thus during proper use, the lower portion 26 of cap skirt 14 must be removed prior to initial closure removal. This is done as indicated in FIG. 3. In FIG. 3, the lower portion 26 of cap skirt 14 is seen to be easily removable by the initial consumer by simply grasping the pull tab 32 and tearing the score line first along branch 28 and then continuing to tear off the lower portion 26 along circumferential score line 22. With the lower interference between structures 20 and 52 thus removed, the closure can now be simply pried off. The remaining interference supplied by interengaging structures 18 and 50 is sufficient to allow the remaining upper portion of the closure to function adequately as a reclosure cap. Further details of the design and operational aspects of the container/closure system embodied in FIGS. 1-4 are taught in U.S. Pat. No. 4,166,552 to Faulstich, which patent is incorporated herein in its entirety by this reference.

By design, the closure/container combination embodied in FIGS. 1-4 functions very well, supplying a secure, reliable and tamper-evidencing closure system. Nevertheless, the system suffers from some deficiencies due primarily to the materials employed and the manufacturing methods required. First, the requirement for the closure material to easily tear along score lines 22/28 normally restricts the material choice to a low-density polyethylene (LDPE) or linear low-density polyethylene (LLDPE). These materials can be generally characterized as relatively pliable or flexible. Second, the containers associated with the combination embodied in FIGS. 1-4 are often fabricated from high-density polyethylene (HDPE). HDPE, while generally more rigid than LDPE or LLDPE, nevertheless is pliable and flexible compared to other typical container materials such as polyethylene terephthalate (PET) or glass. In addition, the processing used to manufacture the containers such as embodied in FIGS. 1 and 2 often emphasizes minimizing material weight, promoting flexibility and pliability of the resulting thin neck finish. This is particularly the case as resin prices continue their unabated upward trend. Finally, the actual process most often used to manufacture the container embodied in FIG. 1, extrusion blow molding, is limited in its ability to consistently achieve tight dimensional tolerances. These factors all additively contribute to the deterioration of the performance expectations of the system.

A particular problem arising from the material choices and process characteristics associated with the embodiments of FIGS. 1-4 is the possibility of a sacrifice in tamper evidency. It has been observed that in certain circumstances, an unscrupulous patron could insert a prying instrument, such as a long fingernail or a screwdriver, between the lower edge 30 of skirt 14 and the exterior surface of the container neck at a point generally indicated by arrow 62 in FIG. 2. Using this leverage to pry up on the lower edge 30, the resulting upward force and distortion of the pliable closure skirt and container neck may be sufficient to release the interference associated with the retention structure and thereby remove the closure without substantial evidence of opening. This is illustrated in FIG. 5. Tool 64 shown in FIG. 5 has sharp end 66 which can be maneuvered under the lower edge 30 of closure 10. Subsequent application of upward force as shown can release the engagement of structures 20 and 52, thereby allowing closure removal without the visual removal of the tear away structure 26.

Efforts have been made to thwart the unauthorized closure removal as described above. Examples of these efforts are illustrated in FIG. 6. In FIG. 6 and future embodiments of this specification, like structural features will be designated by the same numeral along with a letter designating the particular embodiment Comparing FIG. 6 with FIG. 2, the downwardly-outwardly sloping container neck surface shown adjacent to the lower edge of the 30 of skirt 14 in FIG. 2 has widely been replaced with a shelf like surface such as that indicated by numeral 67 in FIG. 6. Surface 67 has a slightly upward-outward slope in the embodiment of FIG. 6, thereby making it more difficult to insert a prying tool without visible damage. This upward slope is indicated by angle “A” in FIG. 6. The angle “A” is typically 5-20 degrees upward from horizontal. In addition, the vertical dimensions for the closure and finish are chosen such that the base of the closure skirt 30 a closely abuts surface 67, thereby further shielding lower edge 30 a. A third design feature embodied in FIG. 6 is a very snug fitting between the interior closure surface 17 a and exterior finish surface 40 a at the lower portion of the closure skirt, generally indicated by the bracket 68 in FIG. 6. While the embodiment of FIG. 6 shows clearance in this region for clarity of presentation, in actual practice surfaces 17 a and 40 a are in contact. Indeed, there often exists a small amount of diametrical interference between the closure skirt and container finish in this region. This snugness further impedes the effectiveness of the pry tool illustrated in FIG. 5.

Another well known proposal to improve tamper evidencing of closure/container systems is taught in U.S. Pat. No. 6,523,710 to Hidding et al. In that patent there is taught a circumferentially extending raised ridge positioned around the periphery of a substantially horizontal shelf like surface. The lower edge of the closure skirt is positioned radially inwardly of the ridge and extends into a concave region formed by the raised ridge and the upward extending exterior surface of the finish. Thus, access to the lower edge of the closure skirt by a prying tool is impeded.

FIGS. 7-11 embody another well known closure and container combination. FIG. 7 is a side elevational view in section of the closure, generally assigned the identification numeral 70. Closure 70 has top 72 generally having the form of a flat disk. Depending from the periphery of top 72 is cylindrical closure skirt 74. Helical engagement structure in the form of threads 75 are positioned on the interior surface of closure skirt 74. Depending from the lower edge 76 of skirt 74 is tamper band 78. Tamper band 78 is attached to skirt 74 by small, frangible bridges 80. Thus bridges 80 and the void sections between bridges 80 form a frangible line of weakness joining the tamper band 78 and skirt 74. Band 78 includes an exterior portion 81 and retaining rim portion 82. In its simplest form, such a retaining rim can include of a single, annular upwardly-inwardly directed structure extending around the interior of tamper band 78. However, in the embodiment shown, retaining rim portion 82 includes multiple upwardly-inwardly extending arcuate segments 84 joined by radially outwardly directed flutes 86. In the embodiment shown, closure 70 has six flutes as best seen in FIG. 9. Retaining portion 82 is joined to exterior portion 81 along a hinge or pivot line 87.

FIG. 10 is a side elevational view, partially in section showing container finish 88 which is complimentary to closure 70. Container finish 88 includes a generally cylindrical wall 90. Threads 92 are positioned on the exterior wall 90. Threads 92 are designed to be complimentary and mate with closure threads 75. In addition, a prominent, outwardly directed bead 94 is positioned below threads 75. The exterior diameter defined by projecting bead 94 is often referred to in the art as the “A” diameter. Bead 94 has downward facing lower locking surface 95.

In the embodiment of FIGS. 7-11, closure application is accomplished by rotating the closure with respect to the container finish to engage the complimentary threads. The axial component of this threading engagement pulls the closure downward to eventually fully seat the closure in sealing position on the container finish. During initial application of the closure, as the thread engagement pulls the closure downward, the retaining portion 82 of tamper band 78 slides over the projecting bead 94. Passage of retaining portion 82 over bead 94 is greatly facilitated by circumferential expansion of the retaining portion due to the ability of the outwardly directed flutes 86 to flex open. Upon full application, the band retaining portion 82 settles beneath the container finish retention bead 94. Upon initial removal, the upward closure movement is resisted by engagement of the upper free edge 85 of retaining rim portion 82 with the lower bottom locking surface 95 of bead 94. This abutment of retaining rim free edge 85 with locking surface 95 prevents the initial removal of the sealing upper portion of the closure without rupturing the bridges 80 and separating the band 78 from the upper sealing portion of the closure.

The closure/container design embodied in FIGS. 7-11 has proven to be an extremely reliable tamper-evidencing system. It has been very successful when the closure is fabricated using relatively rigid materials such as polypropylene. Such materials permit adequate pliability at the hinge line 87 while offering adequate rigidity to prevent unacceptable bending, distortion or collapse of the retaining portion 82 during initial removal. Such bending or distortion could thwart the designed interference intended to produce rupture at the frangible line of weakness.

Further details of the design and operational aspects of the container/closure system embodied in FIGS. 7-11 are taught in U.S. Pat. No. 6,484,896 to Ma, the contents of which patent is incorporated herein in its entirety by this reference.

Turning now to FIG. 12 there is shown a container neck finish 37 b according to one aspect of the current invention. Neck finish 37 b may be used in conjunction with a closure similar to closures similar to that depicted in FIGS. 1-4. The upper portion of novel neck finish 37 b is similar to finish 37 a depicted in FIG. 6, including projections 18 b and 52 b. However, the upward sloping surface 67 of the FIG. 6 finish embodiment has been altered in the inventive FIG. 12 embodiment to add multiple, discrete upward projecting structures 98 positioned circumferentially around the annular surface 67 b. This positioning is best seen in the sectional view of FIG. 13. In the embodiment of FIGS. 12 and 13, structures 98 are presented in the form of hollow, partial spheres. However, any number of multiple, disconnected structural designs can be considered such as truncated cones, truncated spheres, etc. Such multiple, disconnected structures are likely easier to fabricate than the continuous raised ridge as taught in the above-mentioned '710 patent.

In the embodiment of FIGS. 12 and 13, the partial spherical structures 98 could typically have a diameter of about 0.5 mm to about 3 mm, while their height would typically be about 0.5 to about 2 mm. The edge-to-edge spacing, indicated as dimension “S” in FIG. 13, is kept small to restrict the width of an invasive prying tool. Typically, dimension “S” would be less than approximately 5 mm, preferably about 0.5 to 2.5 mm, and most preferably about 1 mm. As shown in FIG. 12, the lower edge of closure skirt 30 b fits snugly between the exterior surface 40 b of container neck finish 37 b and structures 98 to restrict access by a prying tool.

FIG. 14 shows another inventive embodiment designed to improve tamper evidencing of container/closure systems. In the FIG. 14 embodiment, both the neck finish 37 c and the closure skirt 14 c have been altered in a complimentary way in the region designated in FIG. 14 by the bracket 100. As shown in FIG. 14, the inventive embodiment includes a radially inwardly tapered inner skirt 17 c in the region 100. The exterior surface 40 c of neck finish 37 c includes a complimentary inward taper in this region. This tapering of closure and finish surfaces accomplishes two objectives. First, the added sectional mass at the base of the closure skirt increases hoop strength precisely in the region required to resist deformation by a prying tool. Second, should a prying tool be inserted beneath the lower edge 30 c of closure skirt 14 c, the upward force exerted will be counteracted by the horizontal component associated with the mating tapered surfaces.

FIGS. 15 and 16 show yet another inventive embodiment designed to improve tamper evidencing of container/closure systems. In the closure embodiment of FIGS. 15 and 16, the lower skirt portion 26 d includes multiple thin vertical lines of weakness 102 extending upward from the lower edge 30 d of lower skirt portion 26 d. These thinned out vertical lines 102 typically have a sectional thickness (in the radial direction) less than 1 mm, and preferably approximately 0.25 to 0.75 mm. Those skilled in the art will understand that an effort to distort the lower skirt 26 d in a way such as suggested in FIG. 5 will rupture one or more of the vertical lines 102 and thereby give a clear indication of tampering.

FIG. 17 is a side elevational view in section embodying yet another container finish modification to improve the tamper evidencing of container/closure combinations. The closure 10 d of the FIG. 17 combination embodiment is similar or identical to closures 10 a and 10 b of FIGS. 6 and 12 respectively. In the combination embodiment of FIG. 17, the neck finish 37 d has been altered in the region designated by the bracket 104. Rather than the vertical neck finish stretch in this region as was present in the finish embodiments of FIGS. 6 and 12, neck finish 37 d includes an inwardly concave surface resulting in concavity 106. In the FIG. 17 embodiment, the concavity 106 is shown as generally circular, but the concave geometry can take other forms such as rectangular, etc. or combination of multiple contours. This will be understood in light of the teachings to follow. An additional feature of the inventive neck finish 37 d embodied in FIG. 17 is the short vertical stretch 108 extending downward from the lower end of the concavity 106. This stretch 108 has exterior diameter dimension closely matching that of the interior diameter of internal closure wall 17 d vicinal the lower edge 30 d of closure skirt 14 d.

FIG. 18 shows the response of the closure to unauthorized upward prying with tool 64 d. Initially the snug fit between internal closure skirt wall 17 d and finish stretch 108 impedes insertion of the tool 64 d beneath the lower edge 30 d of closure skirt 14 d as taught in previous embodiments. However, if one succeeds in the insertion of the tool underneath the closure skirt 14 d and proceeds to pry upwards, the closure skirt will collapse into the concavity 106 as shown. A portion of the deformed skirt will be pressed against the upper region 110 of the concavity, thereby encountering the horizontal component of this surface region of the concavity. Further upward movement of the closure and any resulting disengagement of the mating retention structures 18 d/50 d and 20 d/52 without substantial is prevented. In the combination embodiment of FIGS. 17 and 18, one takes advantage of the pliability of the material used to make the closure 10 d. In contrast, the finish embodiment of FIG. 6 supplies backing support to the lower portion of the closure skirt in the region identified by bracket 68 of the FIG. 6. While the tight dimensional fitting shown between closure skirt and finish can add frictional resistance to upward closure movement under the forces of a prying tool, the backing support of the finish effectively augments the rigidity of the closure skirt. As one skilled in the art will understand, certain dimensional variations between closure and finish can actually result in such a close fitting arrangement becoming a detriment.

FIG. 19 embodies an extension of the teachings of FIGS. 17 and 18 to another closure system. In the FIG. 19 embodiment, the combination closure 112 includes a fitment 114 along with an additional reclosure cap 116. Bottle fitments of the type shown in FIG. 19 are taught in U.S. patent application Ser. No. 10/854,925 having U.S. Patent Application Publication No. 2005/092750, the entire contents of which are incorporated herein by this reference. The container finish 37 e embodied in FIG. 19 is capable of accommodating both the closures such as closure 10 a of FIG. 6 as well as the fitment style closures taught in the above-mentioned '925 application. As such, neck finish 37 e of FIG. 19 includes multiple concave stretches, in the FIG. 19 embodiment two in number and identified as 118 and 120, positioned vicinal the lower edge of multiple corresponding closure designs.

Referring now to FIGS. 20-23, there is illustrated and embodied a novel inventive closure having improved tamper-evidencing performance. Closure 10 f combines the facile application and proven performance of the push-on/pull-off closure presented in FIGS. 1-4 with the improved tamper features of the closures presented in FIGS. 7-11. In the FIG. 20 closure, the retention structure 20 shown in the closure of FIGS. 1-4 is replaced with the improved retaining structure 82 embodied in the closure of FIGS. 7-11. However, as has been previously noted, the retaining structure of FIGS. 7-11 normally employs materials, such as polypropylene, which are more rigid than those (low-density polyethylenes) required for the push-on and tear away features of the closure of FIGS. 1-4. These low-density polyethylenes do not possess sufficient rigidity to prevent collapse and inversion of the band during prying with a tool such as suggested in FIG. 5. This is especially a problem in that the tear line 22 associated with such closures is much better at retaining its integrity under such strain conditions than the frangible bridges associated with the closures of FIGS. 7-11.

This problem of retainer ring collapse has been addressed in the inventive closure of FIG. 20 by adding small upward extending spike-like extensions 122 emanating from the top free edge surface of the retaining rim. As most clearly shown in the assembly drawing of FIG. 23, these extensions 122 come to rest between the outward container projection 52 f and the inner wall 17 f of the closure skirt when the closure is initially applied. While FIG. 23 shows clearance among the container and closure structures in this region, this clearance is only present in the drawing for clarity of presentation. In actual fact, diametrical dimensions are chosen such that the extension 122 is actually squeezed between container projection 52 f and inner closure wall 17 f. In this way the arcuate segments of the retainer rim 84 f are held rigidly upward and prevented from collapsing when the closure is subjected to unauthorized force in the upward direction.

FIGS. 24-26 present an alternate embodiment according to the same principles explained in conjunction with FIGS. 20-23. In the FIGS. 24-26 embodiment, upward extensions 128 emanate from the pleats joining the arcuate segments 84 g. As best seen in FIG. 26, these pleat extensions 128 become squeezed between container projection 52 g and internal skirt wall 17 g upon initial application of the closure. The squeezing of the pleat extension prevents collapse of the retaining ring thereby ensuring very secure retention of the closure until tear band 26 g has been removed. One will appreciate that other geometric shapes may be utilized for the upward extensions.

For convenience in explanation and accurate definition in the appended claims, the terms “up” or “upper”, “down” or “lower”, “inside” and “outside” are used to describe features of the present invention with reference to the positions of such features as displayed in the figures.

In many respects the modifications of the various figures resemble those of preceding modifications and the same reference numerals followed by subscripts “a”, “b”, “c”, “d”, “e”, “f”, and “g” designate corresponding parts.

The foregoing descriptions of specific embodiments of the present invention have seen presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the invention to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The embodiments were chosen and described in order to best explain the principles of the invention and its practical application, to thereby enable others skilled in the art to best utilize the invention and various embodiments with various modifications as are suited to the particular use contemplated. It is intended that the scope of the invention be defined by the Claims appended hereto and their equivalents. 

1. A tamper-evidencing closure comprising: a top, an annular skirt depending from the top; a tamper-evidencing band frangibly connected to the bottom of the annular skirt; an inwardly-turned retaining rim that extends at least partially upwardly from the tamper-evidencing band, the retaining rim having a free edge adapted for engagement with a locking surface of a container; and an anti-collapsing extension extending from the free edge of the retaining rim; wherein the anti-collapsing extension is dimensioned and configured to oppose collapse and distortion of the retaining rim when an upward force is applied to the closure while the free edge is engaging the locking surface.
 2. A tamper-evidencing closure according to claim 1, wherein the anti-collapsing extension has a rectangular shape.
 3. A tamper-evidencing closure according to claim 2, wherein the anti-collapsing extension has a substantially square-shaped cross-section.
 4. A tamper-evidencing closure according to claim 1, further comprising: a plurality of anti-collapsing extensions extending from the free edge of the retaining rim, the anti-collapsing extensions being circumferentially spaced around the retaining rim.
 5. A tamper-evidencing closure according to claim 4, further comprising: a plurality of flutes located between adjacent arcuate segments of the retaining rim; wherein at least one anti-collapsing extension is located between adjacent ones of said flutes.
 6. A tamper-evidencing closure according to claim 1, further comprising: vertically-extending lines of weakness circumferentially spaced about the annular skirt.
 7. A tamper-evidencing closure according to claim 6, wherein the lines of weakness are located on an inner surface of the annular skirt.
 8. In combination, a tamper-evidencing closure according to claim 1 and a tamper-evidencing container, said container comprising: a container neck finish having closure-engaging structure dimensioned and configured for engaging the closure upon reclosure; and a locking surface on the container neck finish below the closure-engaging structure, the locking surface being dimensioned and configured to engage the free edge of the retaining rim of the closure; wherein the anti-collapsing extension of the closure extends between the locking surface of the container and the annular skirt of the closure when the closure is fully applied to the container.
 9. A combination according to claim 8, further comprising: an inward taper on an exterior surface of the container neck finish below said locking surface, the inward taper being dimensioned and configured to increase hoop strength of the exterior surface.
 10. A combination according to claim 9, wherein the inward taper is formed by an inwardly-concave stretch.
 11. A combination according to claim 10, further comprising another inwardly-concave stretch formed in another exterior surface of the container neck finish, the another inwardly-concave stretch being dimensioned and configured to increase hoop strength of the another exterior surface. 